public int CompareTo(object other)
{
Frequent_Itemset otherTemperature = other as Frequent_Itemset;
if (this.Support == otherTemperature.Support)
{
return(0);
}
if (this.Support < otherTemperature.Support)
{
return(1);
}
return(-1);
}
/// <summary>
/// 生成关联规则
/// </summary>
public void genAssoc_rules()
{
AssociationRule obj_tempAR;
float total_confidence = 0;
ArrayList temp_AR = new ArrayList();
for (int count_ar = 0; count_ar < freq_itemsets.Count; count_ar++)
{
Frequent_Itemset obj = (Frequent_Itemset)freq_itemsets[count_ar];
int first_id = obj._itemid_1; // 第一个项目id
int second_id = obj._itemid_2; // 第二个项目id
float confidence_1 = (float)((float)obj.support_count / (float)getSupport_count(first_id)); // 置信度1
total_confidence += confidence_1;
obj_tempAR = new AssociationRule(first_id, second_id, obj.Support, confidence_1);
temp_AR.Add(obj_tempAR);
float confidence_2 = (float)((float)obj.support_count / (float)getSupport_count(second_id)); // 置信度2
total_confidence += confidence_2;
obj_tempAR = new AssociationRule(second_id, first_id, obj.Support, confidence_2);
temp_AR.Add(obj_tempAR);
}
// 置信度阈值，取平均值
float min_confidence = (float)total_confidence / (float)temp_AR.Count;
AssociationRule.min_confidence = min_confidence;
// 生成关联规则
foreach (AssociationRule obj in temp_AR)
{
if (obj.confidence > min_confidence)
{
association_Rules.Add(obj);
}
}
}
/// <summary>
/// 生成频繁-2项集
/// </summary>
public void genFreq_two_itemsets()
{
int count = 0;
ArrayList temp_freq_itemsets = new ArrayList();
ArrayList count_ArrayList = new ArrayList();
Frequent_Itemset obj_Frequent_Itemset;
Frequent_Itemset[] obj_freq_itemsets;
int count_Support = 0;
float total_Support = 0;
int[] freq_one_items_id = new int[freq_one_items.Count];
for (int n = 0; n < freq_one_items.Count; n++)
{
Freq_Item obj = (Freq_Item)freq_one_items[n];
freq_one_items_id[n] = obj.itemid;
}
for (int n = 0; n < freq_one_items_id.Length - 1; n++)
{
int itemid_1 = freq_one_items_id[n];
for (int m = n + 1; m < freq_one_items_id.Length; m++)
{
int itemid_2 = freq_one_items_id[m];
// 扫描数据集，得到共同用户数目
for (int userid = 1; userid < sourceUsers.Length; userid++)
{
// 如果该用户喜欢这两个项目
if ((discretize[userid][itemid_1] == true) && (discretize[userid][itemid_2] == true))
{
count_Support++;
}
}
// 计算这两个项目的支持度
float support = (float)((float)count_Support / (float)sourceUsers.Length);
obj_Frequent_Itemset = new Frequent_Itemset(itemid_1, itemid_2, count_Support, support);
temp_freq_itemsets.Add(obj_Frequent_Itemset);
total_Support += support;
count_Support = 0;
}
}
obj_freq_itemsets = new Frequent_Itemset[temp_freq_itemsets.Count];
int _count_zero = 0;
foreach (Frequent_Itemset item in temp_freq_itemsets)
{
if (item.Support == 0)
{
_count_zero++;
}
obj_freq_itemsets[count++] = item;
}
Array.Sort(obj_freq_itemsets);
// 计算所有不为零频繁2项集的支持度平均值 设为支持度阈值
float Min_Support = total_Support / (float)(obj_freq_itemsets.Length - _count_zero);
Frequent_Itemset.min_support = Min_Support;
foreach (Frequent_Itemset obj_freq_itemset in obj_freq_itemsets)
{
if (obj_freq_itemset.Support > Frequent_Itemset.min_support) // 支持度大于支持度阈值
{
freq_itemsets.Add(obj_freq_itemset);
}
}
// 最小支持度计数
Frequent_Itemset last_two = (Frequent_Itemset)freq_itemsets[freq_itemsets.Count - 1];
Frequent_Itemset.min_support_count = last_two.support_count;
}
/// <summary>
/// 生成频繁-2项集
/// </summary>
public void genFreq_two_itemsets()
{
int count = 0;
ArrayList temp_freq_itemsets = new ArrayList();
ArrayList count_ArrayList = new ArrayList();
Frequent_Itemset obj_Frequent_Itemset;
Frequent_Itemset[] obj_freq_itemsets;
int count_Support = 0;
float total_Support = 0;
int[] freq_one_items_id = new int[freq_one_items.Count];
for (int n = 0; n < freq_one_items.Count; n++)
{
Freq_Item obj = (Freq_Item)freq_one_items[n];
freq_one_items_id[n] = obj.itemid;
}
for (int n = 0; n < freq_one_items_id.Length - 1; n++)
{
int itemid_1 = freq_one_items_id[n];
for (int m = n + 1; m < freq_one_items_id.Length; m++)
{
int itemid_2 = freq_one_items_id[m];
// 扫描数据集，得到共同用户数目
for (int userid = 1; userid < sourceUsers.Length; userid++)
{
// 如果该用户喜欢这两个项目
if ((discretize[userid][itemid_1] == true) && (discretize[userid][itemid_2] == true))
count_Support++;
}
// 计算这两个项目的支持度
float support = (float)((float)count_Support / (float)sourceUsers.Length);
obj_Frequent_Itemset = new Frequent_Itemset(itemid_1, itemid_2, count_Support, support);
temp_freq_itemsets.Add(obj_Frequent_Itemset);
total_Support += support;
count_Support = 0;
}
}
obj_freq_itemsets = new Frequent_Itemset[temp_freq_itemsets.Count];
int _count_zero = 0;
foreach (Frequent_Itemset item in temp_freq_itemsets)
{
if (item.Support == 0)
{
_count_zero++;
}
obj_freq_itemsets[count++] = item;
}
Array.Sort(obj_freq_itemsets);
// 计算所有不为零频繁2项集的支持度平均值 设为支持度阈值
float Min_Support = total_Support / (float)(obj_freq_itemsets.Length - _count_zero);
Frequent_Itemset.min_support = Min_Support;
foreach (Frequent_Itemset obj_freq_itemset in obj_freq_itemsets)
{
if (obj_freq_itemset.Support > Frequent_Itemset.min_support) // 支持度大于支持度阈值
freq_itemsets.Add(obj_freq_itemset);
}
// 最小支持度计数
Frequent_Itemset last_two = (Frequent_Itemset)freq_itemsets[freq_itemsets.Count - 1];
Frequent_Itemset.min_support_count = last_two.support_count;
}